Method and means for increasing the load capacity of lift trucks



April 23, 1963 Filed Sept. 22, 1960 i111@ Q- Tijl O. F. CHRISTANSENMETHOD AND MEANS FOR INCREASING THE LOAD vCAPACITY OF LIFT TRUCKS 4Sheets-Sheet 1 d/24 Eig 62 ee 22 I4 l 9e FIG. 3 86 INVENTOR.

OVE F. CHRISTIANSEN ATTORNEY April 23, 1963 o. F. CHRISTIANSEN 3,086,618

METHOD AND MEANS EDE INCREASING THE LoAD CAPACITY DE LIFT TRUCKS FiledSept. 22, 1960 l 4 Sheets-Sheet 2 FIG. L

INVENTOR OVE F. CHRIS-HANSEN BY I l( IJ/M4110 ATTORNEY April 23, 1963 F.CHRIS-HANSEN 3,086,618 METHOD AND MEANS FOR INCREASING THE LOAD CAPACITYOF LIFT TRUCKS Filed sept. 22, 1960 4 Sheets-Sheet 5 INVETOR OVE F.CHRISTIANSEN Byf www April 23, 1963 o. F. cHmsnANsN METHOD AND M3,086,618 EANS FOR INCREASING THE LOAD CAPACITY OF LIFT TRUCKS FiledSept. 22, 1960 4 Sheets-Sheet 4 FIG. 6

OVE F.' CHRISTIANSEN Bff/ Wm ATTORNEY United States Patent O ffice3,636,618 METHOD AND MEANS FOR INCREASING THE LOAD CAPACITY OF LIFTTRUCKS Ove F. Christiansen, Soborg, Denmark, assignor to Lars Ambak 8LCompany, Copenhagen, Denmark Filed Sept. 22, 1960, Ser. No. 57,7 14Claims priority, application Denmark Oct. 14, 1959 1S Claims. (Cl. IS7-9) 'This invention relates to a material handling method and means andmore particularly to a method and means utilizing a combination of alift truck and auxiliary apparatus for increasing the normal liftingcapacity of the truck.

j Lift trucks have long been utilized to lift and transport loads ofwidely differing kinds, making possible the rapid and safe move-ment ofmaterials'. Lift trucks are produced in a wide variety of sizes andcapacities, and the cost of such trucks is roughly proportional to thelifting capacity thereof. Minimum capital expense for such equipment isnormally based upon the use of trucks, the capacity of which correspondsto the most frequently occurring load; i.`e., the lifting capacity isnot appreciably greater than the weight of the loads most lfrequentlytransported. i

In large material handling operations which require widely differinglifting capacities, a fleet of such trucks is normally maintained inorder to expeditiously meet the varying requirements. In relativelysmall handling operations, on the other hand, where there may be a needonly for a single truck or for a very few trucks to transport the mostfrequently occurring loads, maintenance of a fleet is not economicallyjustifiable. In many such relatively small operations, however, a needfrequently arises which requires that loads exceeding the capacity ofavailable trucks be transported. Heretofore this problem has been solvedby means of time-consuming and iueicient material handling methods.

The present invention makes available a relatively simple andinexpensive auxiliary apparatus which can be associated in a novelmanner with a lift truck for lifting and transporting loads, the weightsof which far exceed .the present invention is capable of lifting andtransporting loads which exceed by several times the capacity of `thetruck itself.

In such an operation it is generally necessary that the lift truck andassociated apparatus be operated in an essentially horizontal plane.

The apparatus of the invention comprises generally a ,dirigibleframework of generally U-shaped yform which is supported byself-adjusting wheels and has an upright lifting mast of relativelylarge capacity secured adjacent one end thereof. A lift truck of givencapacity may be driven into the pocket of the framework and then coupledtherewith preferably such that the lifting mast of the lift truck ispre-loaded to rated capacity in order to assure `initially full tractionat the drive wheels of the lift truck.

The larger lifting mast of the Iframework may then engage and lift aload substantially heavier than the lift truck alone is capable ofhandling and the lift truck then operated .to transport the frameworkand its load to a desired location at which the load may be deposited atany elevation within the lifting limit of the auxiliary lifting mast.

`The hydraulic system of the lift truck may be coupled `with a liftingmotor of the auxiliary mast for elevating rigid U-shaped frame.

3,086,618 Patented Apnea, 1963 loads thereon. Y Auxiliarykcour'it'erweights are located at the rear of theframework such thatoperation of the framework with the lift truck corresponds at leastin'level movement to a lift truck of vgreater capacity -thanl'thaty usedin the invention.

The invention can be soldat a price which is much lower than the pricedifference between a lift truck of corresponding capacity andthe truckused in the invention. In essence, a lift truck of given capacity can beused in combination with one ormore auxiliary frameworks to perform inthe majority of material handling operations as would two or more lifttrucks of varying capacities. No drive machinery, hydraulic, steering orcontrol systems, and the like, independent of the lift truck used isutilized in the auxiliary framework, and the upright lifting mast of theframework can be of standard construction.

It is a primary object of the present invention to provide a method andmeans which utilizes a lift truck and which substantially increases thenormal lifting capacity thereof.

It is another object of the invention to provide apparatus which can becoupled with a lift truck for operation as an integral part thereof Iforthe purpose of increasing the load capacity normally transportable bythe truck alone.

Another object of the invention is to increase the versatility of thelift trucks by providing a method and means which uses the lift truck totransport loads substantially above the capacity which the truck isnormally capable of handling.

Other objects, features, and advantages of the present invention willappear to persons skilled in the art in view of the followingdescription when taken in conjunction with the drawings wherein:

FIGURE 1 illustrates, somewhat schematically, an exemplary embodiment ofthe invention in side elevation 4shown in coupled relation with a lifttruck;

FIGURE 2 shows a plan view of the auxiliary framework of the inventionas shown in FIG. 1, but without the lift truck being coupled thereto;

FIGURE 3 is an enlarged sectional view taken along line 3-3- in FIG. 2;

, FIGURE 4 shows the actual construction of the invention in sideperspective view with the lift truck in position to enter the U-shapeddirigible framework;

FIGURE 5 shows the construction of FIGURE 4 taken from the opposite sideand with the lift truck embraced by and coupled to the U-shapedframework; and

FIGURE 6 is a rear perspective view of the U-shaped framework.

Referring now in detail to the drawing, a generally U-shape'd frame isdesignated at numeral 10 and includes a pair of spaced parallel legs12and 14 which vare connected rigidly together at the forward ends thereofby a transverse frame or plate member 88. Frame` members `12 and 14 areof generally L-shaped or T-shaped section, as shown in FIGS. 1 and 5,respectively, the upwardly extending legs 18 and 20 of which increase inheight at the forward ends 22 thereof. Transverse frame member 88 ispreferably -about equal in height to forward leg portions 22 and issecured, as fby welding, adjacent the forward ends of portions 22 forproviding a relatively A pair of counterweight members 24 are secured tothe rearwardmost portions of frame membes 12 and 14'ar1d are adapted tobe connected by a removable rod 26 which is secured to the counterweightmembers by means of bolts and brackets 28.

A pair of transversely spaced forwardly projecting upper lugs l30 arewelded to the upper forward surface of member 88 anda pair of similarlyprojecting lower lugs 32 are welded to the lower forward surface ofmember 88. An upper transverse support rod 34 is rigidly secured to theforward ends of lugs 30` and to the after ends of a pair of laterallyspaced rearwardly extending lugs 36 which are secured at their forwardends, as by welding, to a pair of transversely spaced mast channelsections 50 of an upright lifting mast 38. Similarly, a lower transversesupport rod 40 is secured to forwardly and rearwardly extending lowerpairs of lugs 32 and 42, respectively.

A pair of laterally spaced wheel support brackets 44 are journaled uponopposite end portions of rod 40 for pivotal movement in a vertical planetransversely outwardly of frame members 12 and 14. A pair ofselfadjusting or caster wheels l46 are mounted in opposite ends of eachof the brackets 44. The rearwardrnost ends of the frame are supportedalso by a pair of self-adjusting or caster wheels 48. The wheels 46 and48 thus serve to support the entire unit comprising the frame and mast38 with the lifting device connected thereto as described below. Mast 38can be of any conventional standard upright construction. It is shownschematically in FIGS. 1 and 2, and the actual construction thereof isshown in FIGS. 4 to 6. Generally, it comprises the pair of laterallyspaced vertical channel sections 50 which serve to guide the verticalmovements of a lifting carriage assembly 52. Carriage assembly 52 issuspended from a pair of laterally spaced chains 54 which are anchoredat their one ends to the carriage assembly and at their opposite ends toa stationary part of the frame assembly, such as rod 34, FIG. l, or rods55, FIG. 6. The chains are reeved over a pair of sprockets 56 which aremounted on a transverse shaft 58 connected at the center thereof to thepiston rod of a hydraulic hoist motor 60 and guided at its opposite endsby means of `a pair of rollers 61 in the channel sections 50 as shown inFIGS. 1 and 2. The carriage assembly 52, including a pair of fork tines63 supported thereon, is elevated in mast 38 in the usual manner byenergizing hydraulic motor 60 to actuate sprockets 56 upwardly withshaft 58 and thereby elevate the carriage assembly which is mounted forguided movement in channels 50 by means of pairs of vertically spacedrollers 62 disposed on opposite sides of the forward flange of thechannel sections, as shown in FIGS. l and 2. The actual construction ofthe mast 38 is somewhat diiferent in detail, but is conventional andneed not be described further herein.

The opening in the U-shaped frame 10 of the apparatus is such that afork truck of given dimensions (shown generally in broken lines atnumeral 70 in FIG. 1 and in full perspective view in FIGS. 4 and 5) andcomprising the vusual engine and counterweight section 72, an uprightlifting mast 74, a pair of transversely spaced drive wheels 76, a pairof transversely spaced steer wheels 78, a cowl section 80 and anoperators seat 82, can be driven between the frame members 12 and `14with sufficient clearance on either side to permit steering movement ofwheels 78. A coupling between the lift truck and the apparatus of thepresent invention, as described below, is elfected with the fork tinesof the lift truck removed from the lifting carriage thereof as shown inFIG. 4. The carriage is connected for vertical guided movement in mast74 in the usual manner, such as is, for example, carriage 52 mounted inmast 38. The lift truck 70, the lifting capacity of which isconsiderably less than the lifting capacity of mast 38 and carriageassembly 52, may be coupled with the framework 10 by means of theexemplary mechanism best illustrated in FIGS. 3 and 4.

The usual carriage plate or fork bar of the lift truck (to which thefork tines are normally connected) is illustrated at numeral 86.Carriage member 86 extends transversely of the mast 74 and is supportedfor elevating movement in mast 74 by means of a chain and sprocketmechanism 87 which is connected to the carriage member by `a bracket 89and which is elevatable by means of a hydraulic lifting motor 91 mountedin the usual manner in mast 74. A forwardly projecting ilange isprovided at the upper end of flange 88 and at least a pair oftransversely spaced threaded openings 92 are formed therein. An invertedgenerally U-shaped transverse rail 94 embraces projecting portion 90 offlange 88 and provides a space 96 between its rearward downwardlyextending leg and flange 88 which is adapted `to receive carriage memberS6. Transversely spaced en larged openings 98 are formed in the upperbase portion of rail 94 coaxial with openings 92 and through each ofthese passes a heavy bolt 100 which is secured in the aligned opening92. With each bolt 100 is preferably associated a heavy spring 102 whichabuts the upper base portion of rail 94 at its one end and a flange 104at its opposite end held in position by a pair of lock nuts 106.

Lift truck 70 may be coupled with the apparatus 10 by driving the truckforwardly within the opening of the apparatus with the carriage member86 lowered below rail 94 until member 86 abuts flange 88, whereuponmember 86 is raised in mast 74 into the space 96' between flange 88 andthe one leg of rail 94, as shown. The member 86 is actuated upwardlyagainst rail 94 and springs 102 preferably until the springs arecompressed to an extent which establishes a Vertical load on mast 74corresponding approximately to the lifting capacity of truck 70.

When the lift truck and apparatus 10 are thus coupled it will be seenthat apparatus 10, including mast 38 and carriage assembly 52, can bedriven in all directions of movement of which the lift truck 70 iscapable when it is uncoupled from the apparatus 18 and operatingnormally. Forward and reverse movements of the truck are transmittedthrough flange 88 and rail 94 to actuate the apparatus 10 forwardly andrearwardly, while steering movements in lateral directions aretransmitted to apparatus 10 by abutment of one or the other of the sidesof the lift truck with one or the other of frame members 12 and 14. Ifdesired, the side walls of truck 70 may be provided with projectingguide facings 111 of brass or other suitable material for this purpose.

It will be understood that the sides of the truck are adapted to beclosely embraced by frame members 12 and 14 of apparatus 16; space 96provides sufficient clearance with the front rear surfaces of member 86so that member 86 can rtwist within space 96 a suicient amount to permitthe guide facings 111 on the sides of the truck to first abut one or theother of frame members 12 or 14, depending on the direction of steering`movement of the truck. Thus, steering movement of the truck istransmitted to apparatus 10 without transmitting the steering torqueloads through member 86 and rail 94.

It will be noted that the U-shaped frame is dimensioned such that framemembers 12 and 14 have relative- -connected has relatively greatrigidity. This arrangement assures that all of the wheels of frame 10and of the lift truck will maintain contact with the ground in drivingover uneven terrain with a distribution of load appropriate to theterrain. It will be understood that the novel manner of coupling theapparatus 10 with the lift truck whereby the lift truck is pre-loadedessentially to capacity assures full traction between the supportingsurface of the truck and drive wheels 76 during operation with a load oncarriage assembly 52.

On the lift truck 70, as shown in FIG. l, there is mounted -a three-wayvalve which has an inlet conduit 112 communicating with the hydraulicpump of the truck, and outlet conduits 114 and 116 which are connectedwith the lift cylinder of mast 74 and the lift cylinder of mast 38,respectively. Conduit connections 112 and 114 may be standard hydraulicconnections associated with the lift truck, while the conduit 116 andits connection with cylinder 60 is demounta-ble so that -it can becoupled and uncoupled therefrom. In the hydraulic coupling the threewayvalve 110 is first adjusted such that inlet conduit 112 communicateswith conduit 114, whereby the carriage member 86 can be lraised untilthe desired preliminary load is established on .the truck. The valve 110is then actuated to communicate conduit 112 with conduit 116, wherebythe fork truck lift cylinder is blocked so that the; oil pressuretherein and the preliminary load on the truck is maintained, while thelift cylinder 60 and carriage assembly 52 may be elevated with its loadunder pressure from the hydraulic system of the lift truck.

With the apparatus of the present invention it is pos-i sible to liftand transport over an essentially level coursel loads which weighseveral tim'es that normally transportable by the fork truck 70. Aspointed out previously, this is possible because of a power surplusdesigned into lift trucks which affords them the capability of climbingramps and the like with a full load, and it is this power surplus whichis utilized for the lifting and transportation of much greater loadswith the present apparatus.

It is preferable to utilize 'a lifting mast 38 having a capacitycomparable to that which would be normally associated with `a lift truckof correspondingly greatery capacity than truck 70. Inasmuch as the oilpressure normally used in various sizes of lift trucks is essentiallyconstant, it will be apparent that the hydraulic system of lift truck 70can without difficulty provide the necessary pressure to hoist motor 60.Since hoist motor 601 requires a greater volume of oil than the normalquantity of oil carried by lift truck 70, it is desirable to provide thelift truck with an `oil container of correspondingly greater volume.Similarly, it will be expedient to provide for extra cooling of themachinery of the truck, in view of the increased load to be transportedthereby. This can be accomplished, for example, by increasing thediameter or rotating velocity of the ventilator fan blades.

The present invention, is not, of course, intended to be limited to theexemplary embodiment described in detail herein, the construction ofwhich can be rearranged and modified in numerous ways, as will beobvious to persons skilled in the art, within the scope of theinvention. For example, the lifting mast 38 can be made tiltable inrelation to the perpendicular. The preliminary load on the fork truck,which assures its tractive power `and maneuverability, can -beestablished in other ways not herein illustrated as, for example, withthe =aid of a hydraulic jack. It will also be apparent from theprinciples of the invention as set forth in the foregoing, that whilethe resilient coupling provided by bolts 100 and springs 102 isdesirable in providing liexibility in the coupling connection betweenthe lift truck and the framework, it is not required. For instance,Vthebolts and springs could be eliminated and the 4rail 94 welded toflange 88 to provide the space 96. In such an arrangement carriagemember lSti exerts a lifting force against rail 94 as previously, butrail 94 does not move in relation to flange 88. The framework, ofcourse, should be of substantially greater effective weight than thelifting capacity of lift truck 70 so that application of the liftingforce against rail 94 which is equal to the capacity of truck 70 willnot lift the forward end of the framework about the pivot axis of casterwheels 48. Any other suitable coupling construction may be utilized solong as the carriage member of the lift truck is capable of applying alifting force to a portion of the one end of the framework for loadingthe upright of the lift truck and for driving the framework with thelift truc'k in any .desi-red direction. Lifting means :associated withthe mast of the apparatus may be of any suitable type depending uponexisting -material handling problems.

It will now be understood that operation of the lift truck and frameworkin coupled relation does not aect :the basic characteristics of eitherthe lift truck or the framework. That is to say, the lift truck operatesin ya 6 normal manner under load as though it were not coupled to theauxiliary apparatus, and the auxiliary apparatus also operates as anindependent lift truck unit to the extent that the framework, mast andwheels thereof `support and counterbalance the load on the fork tines63.

Therefore, while I have shown and described what I believe to be apreferred embodiment of my present invention, it should Ibe fullyunderstood that many rearrangements and modifications may be madetherein without departing from the spirit and scope of my invention.

I claim:

l. An -apparatus for increasing the normal load capacity of a lift truckcomprising a generally U-shaped frame, wheel means supporting saidframe, elevatable load carrying means supported adjacent one end of saidframe, said frame being adapted to embrace a lift truck having anelevatable load carrying means connected adjacent one end thereof withinthe open pocket of said frame, and means for coupling said frame withthe lift truck for combined operation.

2. An apparatus comprising la generally U-shraped frame, wheel meanssupporting said frame, elevatable load carrying means supported adjacentone end of said fra-me, said frame being adapted to embrace a lift truckhaving an elevatable load carrying means connected adjacent one endthereof within the open pocket of said frame, the load carrying means ofsaid frame being of greater 'load carrying capacity than the loadcarrying means of the lift truck, and coupling means connected to saidframe for receiving a portion of the load carrying means of the lifttruck whereby to couple the lift truck and frame for combined operation.

3. Apparatus for increasing the normal load capacity of a lift :truckcomprising a generally U-shaped fra-me, wheel means supporting saidframe lforwardly and rearwardly thereof, an upright mast assembly forengaging and elevating loads mounted forwardly of said frame,counterweight means mounted rearwardly of said frame, iand couplingmeans mounted adjacent the forward end of said frame, said frame beingadapted to embrace a lift truck having elevatable means mountedforwardly thereof within the open pocket of the frame and forming acoupling between the elevatable means and said coupling means. f

4. Apparatus for increasing the normal capacity load of a materialhandling machine comprising a generally U-shaped frame, wheel meanssupporting said frame for- Wardly and rearwardly thereof, relativelylarge capacity elevator means secured to said frame and mountedforwardly of the base end thereof, counterweight means mounted -adjacentthe end opposite the base end of the frame, said base end includingcoupling mens, said apparatus being adapted to embrace in :the openpocket thereof a material handling machine having elevator meansconnected adjacent the forward end thereof for establishing a couplingrelation with said coupling means.

5. Apparatus for increasing the normal load capacity of a materialhandling machine comprising a wheel supported framework which is adaptedto embrace in an open portion thereof a material handling .machinehaving elevator means associated therewith, coupling means connected tosaid framework adapted to receive a por-tion of said elevator means whenthe material handling machine is located in .the open portion of theframework, and other elevator means supported from said framework forengaging, lifting and transporting loads, said other elevator meansbeing of greater carrying capacity than said first mentioned elevatormeans.

6i. In combination, :apparatus comprising an open ended longitudinallyextending lframe having a transverse means closing one end thereof,wheel means supporting said frame, a load lifting mast assemblysupported forwardly of the closed end of said frame, coupling meansconnected to the closed end of said frame, and a lift truck '7receivable within and embraced by said frame having a lifting mastassembly mounted adjacent one end thereof, a portion of said latter mastassembly being locatable in lifting relation to said coupling means forimposing upon said latter mast assembly a pre-load.

7. A combination as claimed in claim 6 wherein counterweight means aremounted at the ends of said frame opposite .to the closed end thereoffor counterbalancing loads engaged by the mast assembly which issupported from said framework.

8. A combination as claimed in claim 6` wherein hydraulic rhoist motormeans are associated with each of the mast assemblies, valve meansmounted on the lift truck, and conduit means connecting said valve meansto each of said hoist motor means, said valve means being adapted toalternately direct pressure fluid through said conduit means to thehoist motor of 4the lift truck connected mast assembly and to the hoistmotor of the frame connected mast assembly.

9. A combination with a lift `truck having a load lifting mast assemblymounted at one end thereof and carriage means elevatable in said mast,of an apparatus comprising a generally U-shaped wheel supported frameadapted to receive in the open pocket thereof the lif-t truck,counterweight means located on said frame adjacent the open end thereof,a load lifting mast assembly supported from said frame forwardly of theclosed end thereof, said latter mast assembly having greater loadlifting capacity than the lift truck mast assembly, coupling meansassociated with the closed end of said frame and forming an upwardlyextending recess for receiving a portion of the lift truck carriage4means for coupling said apparatus with the lift truck such that saidapparatus can be driven by the lift truck for engaging, lifting andtransporting loads upon the mast assembly connected to said frame, saidcarriage being actuated upwardly in said recess to impose upon the mastassembly of the lift truck a load providing traction at the drive wheelsthereof.

`10. A combination as claimed in claim 9 wherein each of `said mastassemblies includes a load actuating hoist motor means, valve meansmounted on the lift truck, conduit means connecting said valve means toeach of the hoist motors, said valve means being operable to firstdirect pressure fluid to the hoist motor of the lift truck forestablishing a pre-load on the mast assembly thereof upon engagementwith the coupling means and to subsequently direct pressure fluid to theother hoist motor.

11. A combination as claimed in claim 9 wherein said coupling meanscomprises a vertical transverse member closing the one end of theU-shaped frame, a movable member forming therewith said recess, andmeans urging said movable member in a downward direction, said carriagemember when received in said recess being actuatable to move saidmovable member in an upward direction.

12. A method for increasing the normal load capacity of a lift truckhaving drive wheels and a load lifting member at one end comprising thesteps of driving the lift truck inside an open wheel supported frameworkhaving one closed end, elevating the load lifting member to form acoupling with the closed end of the framework and to impose a pre-loadon the lift truck whereby to increase traction at the drive wheelsthereof, and driving said lift truck and said framework together incoupled relation for engaging a load at the forward end of theframework.

13. A method for increasing the normal load capacity of a lift truck-having drive wheels and a load lifting member at one end, by disposingthe lift truck in coupled relation with a wheel supported frameworkhaving one open end and one closed end and a load engaging elevatormounted adjacent the closed end, comprising the steps of driving thelift truck inside the open framework until Ithe lifting member `thereofabuts the closed end of the framework, elevating the lifting member -toform a coupling with the closed end and to tend to lift the frameworkwhereby to impose a pre-load on the lift truck for increasing tractionat the drive wheels thereof, and driving said lift truck and frameworktogether in coupled relation for engaging a load on the frame supportedelevator.

14. A method for increasing lche normal rated load of `a lift truckhaving drive wheels and a load lifting member at one end, by combiningsame with a Wheel supported and counterweighted framework having oneopen and one closed end and a hydraulically actuated load lifting meansmounted adjacent the closed end and of greater lifting capacity than theload lifting member of the lift truck, comprising the steps of drivingthe lift truck into the open end of the framework until the load liftingmember abuts a portion of the closed end thereof, elevating the loadlifting member to form a couple with the closed end and to impose apre-load on the lift truck for increasing traction at the drive wheelsthereof, locking said load lifting member in said elevated position, anddirecting pressure iluid to the hydraulic load lifting means of theframework.

15. A method as claimed in claim 14 plus the step of raising a load onsaid load lifting means of greater weight than can be safely carried bysaid load lifting member, and driving the lift truck and apparatustogether in coupled relation.

References Cited in the file of this patent UNITED STATES PATENTS2,504,885 Schreck Apr. 8, 1950 2,601,163 Millar June 17, 1952 2,684,165Hill July 20, 1954 2,916,172 Locke Dec. 8, 1959 2,944,689 Arnot July 12,1960

1. AN APPARATUS FOR INCREASING THE NORMAL LOAD CAPACITY OF A LIFT TRUCKCOMPRISING A GENERALLY U-SHAPED FRAME, WHEEL MEANS SUPPORTING SAIDFRAME, ELEVATABLE LOAD CARRYING MEANS SUPPORTED ADJACENT ONE END OF SAIDFRAME, SAID FRAME BEING ADAPTED TO EMBRACE A LIFT TRUCK HAVING ANELEVATABLE LOAD CARRYING MEANS CONNECTED ADJACENT ONE END THEREOF WITHINTHE OPEN POCKET OF SAID FRAME, AND MEANS FOR COUPLING SAID FRAME WITHTHE LIFT TRUCK FOR COMBINED OPERATION.